// Copyright(c) 2019 - 2020, #Momo
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// 2. Redistributions in binary form must reproduce the above copyright notice,
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#pragma once

#include "ShaderBase.h"

namespace MxEngine
{
    struct PipelineStageInfo;

    class Shader : public ShaderBase
    {
    public:
        enum PipelineStage
        {
            VERTEX = 0, // should be equal to 0, next to 1, etc.
            GEOMETRY,
            FRAGMENT,
            STAGE_COUNT // should be last
        };
        #if defined(MXENGINE_DEBUG)
        std::array<MxString, PipelineStage::STAGE_COUNT> debugFilePaths;
        MxVector<MxString> includedFilePaths;
        #endif

        static BindableId CreateShaderProgram(ShaderId* shaderIds, const PipelineStageInfo* stageInfos, size_t count);
        void LoadDebugVariables(const PipelineStageInfo* stageInfos, size_t count);
    public:
        void Load(const MxString& vertexPath, const MxString& fragmentPath);
        void Load(const MxString& vertexPath, const MxString& geometryPath, const MxString& fragmentPath);
        template<typename FilePath> void Load(const FilePath& vertexPath, const FilePath& fragmentPath);
        template<typename FilePath> void Load(const FilePath& vertexPath, const FilePath& geometryPath, const FilePath& fragmentPath);

        void LoadFromString(const MxString& vertexSource, const MxString& fragmentSource);
        void LoadFromString(const MxString& vertexSource, const MxString& geometrySource, const MxString& fragmentSource);

        const MxString& GetDebugFilePath(Shader::PipelineStage stage) const;
        const MxVector<MxString>& GetIncludedFilePaths() const;
    };
}
